Beryllium containing rocket propellants producing maximum boost velocity

ABSTRACT

1. In a rocket propellant composition which burns to produce propulsive gases and which consists essentially of a finelydivided, solid, inorganic oxidizer containing combined oxygen which it yields readily for combustion of the fuel components of said composition, and a finely-divided beryllium-containing fuel selected from the group consisting of beryllium, beryllium hydride and mixtures thereof dispersed in an organic fuel matrix comprising at least about 20 per cent by volume of said composition, the improvement in which the oxidizer, the beryllium-containing fuel, and the organic fuel matrix are present in amounts such that the oxidation ratio as defined by the following expression:

Scuirlock et al. I

Sttes BERYLLIIUM CONTAINING ROCKET PROPELLANTS PRODUCING MAXI BOOSTVELOCITY Inventors: Arch Scurlock, Arlington; Keith E.

Rumbel, Oakton; M. Lee Rice, Alexandria, all of Va.

Atlantic Research Corporation, Alexandria, Va.

Filed: Sept. 12, 1963 Appl. No.: 309,369

Related US. Application Data Continuation-in-part of Ser. No. 65,856,Oct. 28, I960, abandoned.

Assignee:

US. Cl l49/19.8, 149/l9.3, l49/19.4, l49/19.5, 149/l9.6, 149/20, 149/38llnt. C1 C0641 5/06 Field of Search 149/17-20, l49/38-44, 87, 97, 98

References Cited UNITED STATES PATENTS 2/1961 Fox 149/19X 7/1961 Hedricketal. 149/19 5/1962 Fox 149/19 6/1963 Hedrick et al. 149/19 [4 June 28,1974 Primary Examiner-Benjamin R. Padgett Attorney, Agent, or FirmMarthaL. Ross EX n CLAIM 1. In a rocket propellant composition which burns toproduce propulsive gases and which consists essentially of afinely-divided, solid, inorganic oxidizer containing combined oxygenwhich it yields readily for combustion of the fuel components of saidcomposition, and a finely-divided beryllium-containing fuel selectedfrom the group consisting of beryllium, beryllium hydride and mixturesthereof dispersed in an organic fuel matrix comprising at least about 20per cent by volume of said composition, the improvement in which theoxidizer, the beryllium-containing fuel, and the organic fuel matrix arepresent in amounts such that the oxidation ratio as defined by thefollowing expression:

O/O C M equals about 0.47 to 0.60

wherein 0 equals the total amount of combined oxygen in the composition,C equals the total amount of carbon, and M equals the amount ofberyllium, said O, C and M being expressed in terms of the number ofatomic equivalents.

20 Claims, 5 Drawing Figures DIBUTYL PHTHALATE 50 5515) STOICHIOMETRICT0 Ii Bel] Pmmimuuze m4 1821.041

' sum 1 or 5 gig. 1

III DERI 20 PARTS BY WT POLYURETHANE OXIDIZERI NH OIO STOIOHIOM I0 TO0O&Be0

SPECIFIC IMPULSE LB- SEC/ L8 264 OXIDAT N RATIO I0 I2 l4 I6 I8 20 22 249600 BERYLLIU CONTENT WT% OXIDATION RATIO 9400 BOOST VELOCIT FT/SEC (M/V INVENTORS.

ARCH 0. SOURLOOK, KEITH E.RUMBEL d MILLARD LEE RICE AGENTPATEIITEIJJURZB ism SHEET 3 OF 5 E D) m 0 n0 5 0 L V 7J 4 W( E O A P I DAO Y m BIL UH T N 0.. DH Z D VA 0 BINDER.

e B a 0 C 0 T m R T E M 0 H C 0 T S 00 00 T T T 2 2 2 at 2 OXIDATIONRATIO I2 INT /o BERYLLIUM OXIDATION RATIO A tlfimw isi 83E E G 508 w mA.

TNVENTORS. ARCH O. SCURLOOK, KEITH E. RUMBEL d MILLARD LEE RICE BY AGENTRATEHTEBJUN 2 8 1974' 3 82 1; 041

sum 0 OF 5 BINDER; 50% BY WT NITROCELLULOSE TRIM THYLOLETHANETRINITRATE(50 70) OXIDIZER NH CIO STOIOHIOMETRIC TO 00 & BeO

SPECIFIC IN I E LB-SEC/LB OXIDATION RATIO l4 I5 I6 I? WT% BERYLLIUMHYDRIDE OXIDATION RATIO 0ST VELOCITY FT/SEC INVENTORS. ARCH 0. SOURLOCK,KEITH E. RUMBEL"d MILLARD LEE RICE AGENT PJTIEIITEDJUTI 28 I974 RELATIVEBOOST VELOCITY, AU/AU REFERENCE SHEET 5 OF 5 BINDER OXIDIZER METALLICFUEL KIND PERCENTAGE KIND PERCENTAGE KIND PERCENTAGE ARCITEQ ARCITEO PlBPIB ARCITE ARCITE ARCITE C b.POLYISOBUTY I8.0 I5.0 I5.0

HYDRIDE QEQUAL PARTSLPIZOIEEVINYL CHLORIDE & DIBUTYL SEBACATE c.43.lPERCENT POLYVINYL CHLORIDE A 56.9 /o DIOCTYL ADIPATE BERYLLIUM ZIRCONIUMBERYLLIUM ARC|TE4 NH4CIO4- BAH; .Isp 299, p= 0.0002

ARGITE -NH GI04 BERYLLIUM, Isp=275,

GO Q \//POLYISOBUTYLENE- NH4GI04 Tsp- I T l I l REFERENCE. ARCITE- NHGIO ,Isp'=258lb sec/lb P=0.0625 Ib/CU IN QDQOOO name-b ARC/T I NHNOS IP=220 MASS RATIO FOR REFERENCE PROPELLANT I II'IIIII MASS-TO-VOLUMERATIO, M /V LB INERT PARTS/GU FT PROPELLANT INVENTORS. ARCH C. SCURLOCK,KEITH E RUMBEL "nd MILLARD LEE RICE IOOO 2000 5000 AGENT g l BERYLLHUM(IONTAINING ROCKET PROPELLANTS PRODUCING VELOCITY This application is acontinuation-impart of application Ser. No. 65,856 to Arch C. Scurlock,Keith E. Rumbel and Millard Lee Rice, filed Oct. 28, 1960 now abandoned.

This invention relates to new propellent compositions. Morespecifically, it relates to beryllium-and beryllium hydride-containingpropellent compositions of exceedingly high propulsive performance.

The term propellant, as employed herein, refers to compositionscomprising an organic fuel binder or matrix containine molecularlycombined carbon and hydrogen, an oxidizer, and a particular finelydivided metal or metal hydride fuel. When introduced into the combustionchamber of a rocket motor and ignited, such compositions generate hightemperature gases, which vent out through the restricted nozzle of themotor at a high velocity to product thrust.

The parameter generally accepted as indicative of the propulsiveperformance of a rocket propellant is its specific impulse, which isdefined as the lbs. of thrust generated per lb. of propellant persecond. Although this characteristic of the propellant is very importantas a criterion for evaluating its performance, specific impulse is notthe sole factor determining optimum performance in a specificapplication where the rocket system as a whole, including its insertparts, such as weight of the motor casing and payload, must beconsidered.

The usual objectives of rocket propulsion are the following:

l. Maximization of altitude and distance attained 2. Minimization oftime-to-target 3. Maximization of thrust Each of these objectives isaccomplished by maximizing the boost velocity imparted to the rocketdevice by combustion of the propellant, the boost velocity being thevelocity of the rocket at burn-out less velocity at launching.

We have found that the relationship between boost velocity and thecharacteristics of the propellant, obtained by applying Newtons secondlaw of motion to the rocket, is defined, for an idealized rocket free ofgravitational and drag effects and pressure thrust, by the followingequation:

Au 1,, log 1 /wv where AU boost velocity velocity at burn-out lesslaunching velocity M mass of inert parts including payload mass ofrocket less mass of propellant V volume occupied by propellant I,specific impulse of the propellant g, dimensional conversion factor,32.17 (lb. mass) (ft)/(lb. force) (see) p density of propellant M /Vmass-to-volume ratio From this expression of the relationships whichdetermine boost velocity, it will be seen that two additional factors,the density of the propellant and the ratio of the mass of inert partsto the volume of propellant enclosed within the motor, becomeexceedingly important, particularly at high M.-/V values, as in the caseof boosters and JATOs. In fact, a propellant of high specific impulse,but low density can be distinctly undesirable for use at high M,/v,,ratios because of a marked drop in boost velocity efficiency.

The specific impulse of the propellant is, however, an exceedinglyimportant factor in determining boost velocity at any M /V ratio. Apropellant having a high specific impulse and producing optimum boostvelocity at formulations coincident with optimum specific impulse is ofgreat value to the rocket art, particularly in applications requiringhigh propulsive performance.

The object of this invention is to provide propellant compositions ofhigh specific impulse which produce maximized boost velocities over awide range of M /V ratios.

Other objects and advantages will become obvious from the followingdetailed description and the drawings in which:

FIGS. 1 through 4 are graphs comparing performance in terms of boostvelocity and specific impulse of propellant formulations containing Beor Be H in different organic binders.

FIG. 5 is a graph comparing the performance of several propellants ofdifferent specific impulse and density at different ratios of the massof the inert parts of the rocketvehicle to volume of propellant.

Broadly speaking, the invention comprises propellent compositionsconsisting essentially of a finely divided, solid, inorganic oxidizerand finely-divided beryllium, beryllium hydride or mixtures of the twodispersed in an organic fuel matrix containing molecularly combinedcarbon and hydrogen, in which the oxidizer and fuel components arepresent in a particular ratio by weight in terms of the number of atomicequivalents, defined as follows:

Oxidation Ratio 0/0 C M (v)/(2) about 0.47 0.60 preferably 0.47 0.55

wherein 0 equals the total amount of oxygen in the propellentcomposition, C equals the total amount of carbon; M equals the totalamount of Be calculated as free metal; and v equals 2, the valence ofBe. Thus in the case of the following reaction:

C-i-Be+20=CO+BeO the Oxidation Ratio 2/2 l l (2)/(2) 0.5

All molecularly combined oxygen, both in the inorganic oxidizer and inthe organic fuel matrix, is included in the determination of totaloxygen. Oxygen available for oxidation reaction, as, for example, theactive oxygen present in the inorganic oxidizer or in an organiccompound, such as a nitrate or nitrite derivative, functions to oxidizemolecularly-combined carbon to CO and the metal fuel component to itsoxide. Oxygen molecularly bonded to a carbon atom in an organic fuelcompound, as, for example, in the case of an ether, alcohol, aldehyde,ketone, ester, amide, etc., though not available for combustion,nevertheless results, by decomposition reaction, in the formation of CO,the desired propulsive gas product. in cases such as organic acids,where decomposition might normally result in the production of CO underthe conditions defined above for the Oxidation Ratio, one of the oxygenatoms preferentially combines with the metal fuel component.

When the components are present in a ratio by weight such that theOxidation Ratio, as defined above,

is 0.5, which will hereinafter be termed as OMOx formulation, the oxygenavailable for combustion of the fuel is stoichiometrically sufficient tooxidize the carbon not already linked to oxygen in the organic fuel toCO and the metal to its oxide. Under such conditions, the molecularlycombined hydrogen in the organic fuel compound and in the berylliumhydride, if the latter is used, after ignition of the propellentcomposition, forms free hydrogen gas, since the molecularly combinedcarbon and the Be react preferentially with oxygen relative to thehydrogen. The hydrogen gas evolved is heated to a high temperaturebecause of the high exotherm of the oxidizing metal. This, and its lowmolecular weight make it a very efficient thrustproducing component inthe combustion reaction product.

We have discovered that propellent formulations containing finelydivided Be, Be H or mixtures of the two as highly exothermic fuelcomponents, have maximum specific impulse and impart optimum boostvelocity to the rocket system when the ratio of oxygen to fuel (organicand metal) is at OMOx or closely approaches OMOx, namely where theOxidation Ratio equals about 0.47 to 0.60 and, in some applications,preferably about 0.47 to 0.55. The Be fuel, in such formulations, hasthe additional, highly advantageous characteristic of forming a highlystable refractory oxide which does not decompose or vaporize to anysubstantial degree after formation, either under the high temperature,high pressure conditions prevailing in the combustion chamber or duringventing of the combustion gases out of the nozzle. Dissociation and/orvaporization of the metal oxide are undesirable since such phenomenaabsorb substantial amounts of heat energy, thereby reducing thetemperature and pressure of the low molecular weight thrust-producingcombustion gases.

These findings are graphically illustrated by the data summarized on thegraphs of FIGS. 1, 2, 3, and 4. FIG. 1 shows the curves for specificimpulse and boost velocity of formulations comprising Be and ammoniumperchlorate in a polyurethane fuel binder. This binder comprises amixture of 56.6 percent P-2 prepolymer (polypropylene glycolprepolymerized with an excess of tolylene diisocyanate; molecular weight2025), 13.7 percent castor oil, 28.1 percent dioctyl azelate, 0.15percent ferric acetyl acetonate, 1 percent lecithin, and 0.7 percentphenyl-B-naphthylamine. FIGS. 2 and 3 summarize similar data forformulations employing a double base binder consisting of nitrocellulosegelled with a mixture of nitroglycerine and dibutyl phthalate and abinder comprising polyvinyl chloride plasticized with dioctyl adipate,respectively. FIG. 4 compares the specific impulse and boost velocity offormulations comprising a double base binder consisting ofnitrocellulose and trimethylolethanetrinitrate, ammonium perchlorate andberyllium hydride. All data were determined assuming shifting chemicalequilibrium. The boost velocity was determined at an MJV ratio of 60lbs/cu ft in FIGS. 1 and 2, and at an M /V ratio of 25 lbs/cu ft inFIGS. 3 and 4. It will be noted that in all of the formulations, thehighest specific impulse and the highest boost velocity are obtainedwithin the Oxidation Ratio range of 0.47 to 0.60 with the peak at orvery close to OMOx. Both the specific impulse and the boost velocity arevery high, in the case of the berylliumpolyurethane composition themaxima being 283 lbsec/lb and 9,160 ft/sec respectively, in the case ofthe beryllium-double base composition 280 lb-sec/lb and 9,185 ft/sec, inthe case of the plasticized berylliumpolyvinyl chloride formulation280.1 lb-sec/lb and 14,840 ft/sec, and in the case of the berylliumhydridedouble base formulation 312.2 lb-sec/lb and 14,375 ft/sec.

It will further be noted that the curves for maximum boost velocityconform very closely to those for maximum specific impulse, acharacteristic which is highly advantageous since such propellentcompositions provide consistently high performance over a broad range ofM /V ratios.

FIG. 4 compares the performance of a number of propellent compositionsrelative to a reference propellant, on propulsion of an idealized rocketvehicle, i.e., one in which the effects of drag, gravity, and pressurethrust are neglected, exhausting to 14.7 psi from a combustion chamberpressure of 1,000 psi. It will be noted that the beryllium-and berylliumhydride-containing propellents show consistently high performance interms of boost velocity relative to that of the reference propellant,whereas the very dense Zr-containing propellant, while exceedinglyeffective at high M /V ratios, drops rather sharply in performance atlow ratios and the low-density propellant comprising a mixture of liquidoxygen and hydrazine, while performing well at low M,-/V ratios, dropssharply in boost velocity performance at high ratios.

As aforementioned, the organic fuel matrix can be any suitable organiccompound or mixture of organic compounds which contains molecularlycombined carbon and hydrogen, so that at OMOx stoichiometry it burnsand/or decomposes to produce CO and free hydrogen gas. It can be inert,the term inert as used herein meaning a compound which requires anexternal source of oxygen, namely the solid, inorganic oxidizer, forcombustion. Illustrative of suitable organic matrix compositions are thevarious solid polymeric binders, such as polyether, polysulfides,polyurethanes, butadiene-acrylic acid and -methacrylic acid copolymerscross-linked with an epoxy, alkyd polyesters, polyamides, celluloseesters, e.g., ethyl cellulose, polyvinyl chloride, asphalt, and thelike. The oxygen linked to carbon in a variety of such inert fuelbinders produces CO by decomposition reaction.

Many of the solid polymeric binders preferably include high-boiling,organic, liquid plasticizers to improve physical properties andprocessing of the propellent composition. Any of the numerous organicplasticizers known in the art and compatible with the propellentcomposition can be employed. Illustrative examples of suitable organicplasticizers include sebacates such as dibutyl sebacate and dioctylsebacate; phthalates, such as dibutyl phthalate and dioctyl phthalate;adipates, such as dioctyl adipate; glycol esters of higher fatty acids,and the like.

The organic fuel matrix can also comprise an active organic compound, amixture of such compounds, or a mixture of such a compound with an inertorganic com pound, such as an inert organic plasticizer, the termactive" compound as employed herein meaning a compound which containsmolecularly combined oxygen available for combustion of other componentsof the molecule, such as carbon. Examples of active organic fuelcompounds include those containing nitroso, nitro, nitrite, and nitrateradicals, such as cellulose nitrate, nitroglycerine,trimethylolethanetrinitrate, diethyleneglycoldinitrate and the like.

The foregoing description has dealt mainly with solid propellentcompositions in which the organic fuel binder is a solid. The inventioncan also be employed in semi-solid, composite monopropellent systems.Such compositions are thixotropic, cohesive, shape-retentivecompositions which can be extruded under moderate pressures into thecombustion chamber of a rocket, where they form continuously advancingcolumns which burn on the exposed surface. In accordance with thisinvention, such plastic monopropellent compositions comprise a stabledispersion of a finely divided, insoluble oxidizer and thefinely-divided Be, Be H or mixtures of the two in a continuous matrix ofany suitable high-boiling organic liquid fuel containing molecularlycombined carbon and hydrogen. Illustrative of suitable liquid fuels arehydrocarbons, such as triethyl benzene, liquid polyisobutylene, and thelike; organic esters, such as dimethyl maleate, dibutyl oxalate, dibutylphthalate and nitroglycerine; alcohols, such as benzyl alcohol andtriethylene glycol; ethers, such as methyl B-naphthyl ether; and manyothers.

Any solid inorganic oxidizer can be employedwhich yields oxygen readilyfor combustion of the metal fuel component and the organic matrix, wherethe latter contains no oxygen or insufficient oxygen for COstoichiometry. Such oxidizers include the inorganic oxidizer salts, suchas Nl-l K, Na, and Li perchlorates and nitrates, metal peroxides, suchas CaO BaO and Na O nitronium perchlorate, hydrazine nitrate, hydrazinenitroform and the like, the salts being preferred.

Where the organic fuel matrix contains molecularly combined oxygenavailable in at least the stoichiometric amount required for oxidationand/or decomposition of the molecularly combined carbon component to CO,no inorganic oxidizer need be provided for its combustion. if suchcombined oxygen is present in amounts greater than that required forsuch stoichiometry, the amount in excess preferentially oxidizes thepowdered metal component rather than the molecularly combined hydrogenand thus can replace a portion of the inorganic oxidizer which wouldnormally be required to oxidize the metal.

The organic fuel matrix, whether it be inert or active, solid or liquid,as aforedescribed, must comprise at least about percent, in some casespreferably at least 30 percent, by volume of the propellent composition.This is essential both to provide for generation of an adequate amountof low molecular weight combustion gases requisite for effectivepropulsion and for processing of a cohesive propellent compositionhaving good physical properties.

The amounts of Be, Be H or mixtures of the two and solid, inorganicoxidizer employed must be such as to produce, with the particular kindand concentration of organic matrix, an Oxidation Ratio within thespecified range of about 0.47 to 0.60. This can readily be calculated byuse of the equation given above for determination of this expression.

The following examples are illustrative of ropellant formulations withinthe scope of the invention:

Example 1 prepared by mixing the following components and then curingthe mixture to form a polyurethane binder by reaction of the P-2prepolymer with the castor oil polyol.

Weight *PZ prepolymer l 1.27 Castor Oil 2.74 Dioctyl azelate 5.62 Ferricacetonyl acetonate 0.03 Lecithin 0.20 Phenyl-Bmaphthylamine 0.14 Be13.01 NH,C10., 66.99

" P-2 prepolymer: polypropylene glycol prepolymerized with an excess oftolylene diisocyanate. Molecular weight 2025.

The burning rate of this OMOx formulation in the motor was 0.217 in/secat a combustion chamber pressure of 1,070 psi.

Example 2 A solid propellent grain was made from a compositioncomprising:

Weight Nitrocellulose 12.6%N)

(Spheres about 15 microns in diameter) 23.88 Nitroclycerine/dibutylphthalate 75/25 containing 1% 2- nitrodiphenylamine 28.08 Dibutylsebacate 2.76 2-Nitrodiphenylamine 0.83 Be 12.75 NH,ClO,, 31.70

Example 3 A solid propellent grain was made from a compositioncomprising:

Weight Nitrocellulose (12.6%N)

(Spheres about 15 microns in diameter) 20.0 Nitroglycerine 21 .0 Dibutylphthalate 9.0 NH,C10 35.1 Be 14.9

The propellant was prepared by the plastisol method. The components weremixed at room temperature and the mixture was then placed in a mold andcured by heating to dissolve the nitrocellulose in the nitroglycerineand dibutyl phthalate plasticizers. The Oxidation Ratio of thiscomposition was OMOx. Burning rate of the grain at F and 1000 psi was0.57 in/sec.

Example 4 A solid propellant-grain was tion comprising:

made from a composi- The propellant was prepared according to theplastisol method by blending the components at room temperature, pouringthe mixture into a mold and heating to dissolve the PVC in the liquidplasticizer, thereby forming a rigid gel. The Oxidation Ratio was OMOx.Burning rate at 70F and 1,000 psi was 0.49 in/sec.

Example A solid propellant grain was made from a composition comprising:

Weight 7:

Nitrocellulose (12.6%N)

(Spheres about microns in diameter) 18.90 Trimethylolethanetrinitrate48.80 Diethyleneglycoldinitrate 8.20 Ethyl centralite 1.20 Alkyl arylpolyether alcohol wetting agent 0.20 Be H 14.70 NH ,ClO 8.00

The propellent was prepared by the plastisol method. The components weremixed at room temperatures and the mixture was then placed in a mold andcured by heating to dissolve the nitrocellulose in thetrimethylolethanetrinitrate and diethyleneglycoldinitrate plasticizers.The Oxidation Ratio of this formulation was OMOx. Burning rate of thegrain in the motor was 0.500 in/sec at a pressure of 1,055 psia and0.860 in/- sec at a pressure of 1,850 psia.

Example 6 A solid propellant grain was made from the followingcomposition:

Weight 7:

Nitrocellulose 12.671N) (Spheres about 15 microns in diameter) 13.47Trimethylolethanetrinitrate 34.71 Diethyleneglycoldinitrate 5.83 Ethylcentralite 0.82 Alkyl aryl polyether alcohol wetting agent 0.17 Be H 11.10 Be 6.20 NH,C10. 27.70

The propellant was prepared by the plastisol method as described inExample 5. The Oxidation Ratio of the combined oxygen which it yieldsreadily for combustion of the fuel components of said composition, and afinely-divided beryllium-containing fuel selected from the groupconsisting of beryllium, beryllium hydride and mixtures thereofdispersed in an organic fuel matrix comprising at least about 20 percent by volume of said composition, the improvement in which theoxidizer, the beryllium-containing fuel, and organic fuel matrix arepresent in amounts such that the Oxidation Ratio as defined by thefollowing expression:

O/O C M equals about 0.47 to 0.60

wherein 0 equals the total amount of combined oxygen in the composition,C equals the total amount of carbon, and M equals the amount ofberyllium, said O, C and M being expressed in terms of the number ofatomic equivalents.

2. The propellant composition of claim 1 in which the organic fuelmatrix comprises at least about 30% by volume of the composition.

3. The propellant composition of claim 1 in which theberyllium-containing fuel is beryllium.

4. The propellant composition of claim 1 in which the expression: O/O CM equals about 0.47 to 0.55.

5. The propellant composition of claim 1 in which the Oxidation Ratioequals about 0.5.

6. The propellant composition of claim 1 in which theberyllium-containing fuel is beryllium hydride.

7. The propellant composition of claim 1 in which theberyllium-containing fuel is a mixture of beryllium and berylliumhydride.

8. In a rocket propellant composition which burns to produce propulsivegases and which consists essentially of a finely-divided, solid,inorganic oxidizing salt containing combined oxygen which it yieldsreadily for combustion of the fuel components of said composition, and afinely-divided beryllium-containing fuel selected from the groupconsisting of beryllium, beryllium hydride, and mixtures thereofdispersed in a fuel matrix consisting essentially of an organic polymer,said fuel matrix comprising at least 20 percent by volume of saidcomposition, the improvement in which the oxidizer, theberyllium-containing fuel, and the fuel matrix are present in amountssuch that the expression of the Oxidation Ratio O/O+ C M equals about0.47 to 0.60, wherein 0 equals the total amount of combined oxygen inthe composition, C equals the total amount of carbon, and M equals theamount of beryllium, said O, C, and M being expressed in terms of thenumber of atomic equivalents.

9. The propellant composition of claim 8 in which the fuel matrixcomprises at least 30 percent by volume of the composition.

10. The propellant composition of claim 8 in which the expression O/O+ CM equals about 0.47 to 0.55.

11. The propellant composition of claim 10 in which the expression O/O CM equals about 0.5

12. The propellant composition of claim 10 wherein saidberyllium-containing fuel is beryllium.

13. The propellant composition of claim 12 wherein said fuel matrixcontains nitrocellulose.

14. The propellant composition of claim 12 wherein said oxidizing saltis ammonium perchlorate. 15. The propellant composition of claim 10 inwhich said beryllium-containing fuel is beryllium hydride.

and beryllium hydride.

19. The propellant composition of claim 18 in which said fuel matrixcontains nitrocellulose.

20. The propellant composition of claim 18 in which said oxidizing saltis ammonium perchlorate.

1. IN A ROCKET PROPELLANT COMPOSITION WHICH BURNS TO PRODUCE PROPULSIVEGASES AND WHICH CONSISTS ESSENTIALLY OF A FINELY-DIVIDED, SOLID,INORGANIC OXIDIZER CONTAINING COMBINED OXYGEN WHICH IT YIELDS READILYFOR COMBUSTION OF THE FUEL COMPONENTS OF SAID COMPOSITION, AND AFINELY-DIVIDED BERYLLIUMCONTAINING FUEL SELECTED FROM THE GROUPCONSISTING OF BERYLLIUM, BERYLLUM HYDRIDE AND MIXTURES THEREOF DISPERSEDIN AN ORGANIC FUEL MATRIX COMPRISING AT LEAST ABOUT 20 PER CENT BYVOLUME OF SAID COMPOSITION, THE IMPROVEMENT IN WHICH THE OXIDIZER, THEBERYLLIUM-CONTAINING FUEL, AND THE ORGANIC FUEL MATRIX ARE PRESENT INAMOUNTS SUCH THAT THE OXIDATION RATIO AS DEFINED BY THE FOLLOWINGEXPRESSION:
 2. The propellant composition of claim 1 in which theorganic fuel matrix comprises at least about 30% by volume of thecomposition.
 3. The propellant composition of claim 1 in which theberyllium-containing fuel is beryllium.
 4. The propellant composition ofclaim 1 in which the expression: O/O + C + M equals about 0.47 to 0.55.5. The propellant composition of claim 1 in which the Oxidation Ratioequals about 0.5.
 6. The propellant composition of claim 1 in which theberyllium-containing fuel is beryllium hydride.
 7. The propellantcomposition of claim 1 in which the beryllium-containing fuel is amixture of beryllium and beryllium hydride.
 8. In a rocket propellantcomposition which burns to produce propulsive gases and which consistsessentially of a finely-divided, solid, inorganic oxidizing saltcontaining combined oxygen which it yields readily for combustion of thefuel components of said composition, and a finely-dividedberyllium-containing fuel selected from the group consisting ofberyllium, beryllium hydride, and mixtures thereof dispersed in a fuelmatrix consisting essentially of an organic polymer, said fuel matrixcomprising at least 20 percent by volume of said composition, theimprovement in which the oxidizer, the beryllium-containing fuel, andthe fuel matrix are present in amounts such that the expression of theOxidation Ratio O/O+ C + M equals about 0.47 to 0.60, wherein O equalsthe total amount of combined oxygen in the composition, C equals thetotal amount of carbon, and M equals the amount of beryllium, said O, C,and M being expressed in terms of the number of atomic equivalents. 9.The propellant composition of claim 8 in which the fuel matrix comprisesat least 30 percent by volume of the composition.
 10. The propellantcomposition of claim 8 in which the expression O/O + C + M equals about0.47 to 0.55.
 11. The propellant composition of claim 10 in which theexpression O/O + C + M equals about 0.5.
 12. The propellant compositionof claim 10 wherein said beryllium-containing fuel is beryllium.
 13. Thepropellant composition of claim 12 wherein said fuel matrix containsnitrocellulose.
 14. The propellant composition of claim 12 wherein saidoxidizing salt is ammonium perchlorate.
 15. The propellant compositionof claim 10 in which said beryllium-containing fuel is berylliumhydride.
 16. The propellant composition of claim 15 in which said fuelmatrix contains nitrocellulose.
 17. The propellant composition of claim15 in which said oxidizing salt is ammonium perchlorate.
 18. Thepropellant composition of claim 10 in which said beryllium containingfuel is a mixture of beryllium and beryllium hydride.
 19. The propellantcomposition of claim 18 in which said fuel matrix containsnitrocellulose.
 20. The propellant composition of claim 18 in which saidoxidizing salt is ammonium perchlorate.